Ignore PyCharm files and remove old ones.
update requirements (need dbus-python)
Revert "update requirements (need dbus-python)"

This reverts commit 5f05f85e1d20c9b11946506c2f25a808c87db78e.

I've been secretly planning to drop DBus. The original commit makes sense
in light of the fact Jamie didn't know my plan, but it's probably better
to use git to revert the change, since that's what git is for.
Merge branch 'visX-devel' of github.com:crantila/vis into visX-devel